Trouble
by ShadowMemory
Summary: Apparently, heroes don't get vacations. Earth is under threat again, but who is the real enemy? Who can be trusted? Blood is spilled and old wounds reopened. The past cannot be ignored, but the future carries as much pain as the present. Humour, epic battles, a pissed off Director Fury, and and a badass OC who sacrifices everything; perhaps in vain. Will it be enough in the end?
1. Investigation

**Hello! This is my first fic, and I'm quite excited about it. Took me a long while to write and hopefully you'll like it. If not, then...Well, there's plenty of ice cream in my freezer for that. Let me know what you think. Constructive criticism is good stuff and helps the writing process. I value your opinion if you aren't a dick about it. Right, I'll shut up and let you read.**

**-Shadow**

* * *

It was the year 2014, and strangely enough, the world hadn't ended in fire and other slightly-less-pleasant things. Hooray. But then again, the world wasn't safe from various other threats either unfortunately, and so that, my dear readers is precisely why there was an emergency meeting at a top secret location. Really top secret. Like James Bond "If I told you I'd have to kill you" type stuff. I'm not kidding.

I think it's somewhere in New York. Anyway-

In one of the many S.H.I.E.L.D headquarters, deep in a maze of offices, laboratories and official looking people running around and doing official looking business, the Avengers were in the process of assembling...again.

'Have you got any idea what this is about?' Steve whispered to Tony, who was busy stuffing his face with peanuts.

'No idea. Whatever it is, it's gotta be serious: Blackbeard doesn't look happy.' He mumbled in reply as they walked into the room, earning a cold and unamused glare from the director. Agent Hill however, who was standing beside him, couldn't help but smirk a little.

'I have asked you all to be here because we have recently discovered a threat to our planet.' Fury began, once everyone had sat down in the conference room.

'What kind of threat exactly?' Tony asked.

'A foreign one.'

'Oh no. Not more Spanish! There's plenty of them here already! I don't think we can cram any more into Mexico.' He complained.

'We're talking foreign on a galactic scale Stark.'

'Oh. Well, olé' He said miserably, arching an eyebrow and sighing. More aliens; just what they needed.

'Hang on a minute, are you saying what I think you are?' Clint piped in.

'If you mean another dangerous alien life form or technology on our planet then yes, I am saying precisely that.' Fury declared solemnly, causing varied responses among the team.

'What exactly are we dealing with?' Natasha requested, wanting to get straight to the point.

'Our scientists have recently been tracking a sudden rise in energy nearby. We don't know what it is or what's causing it. Hell, we hardly know anything about it. It's random, but seems to have calmed down now at least.'

There were a few moments of quiet. The silence was broken when a man walked in with a worried expression.

'Sir, it's active again. We've just noted a massive peak in energy and it doesn't seem to be fading this time.'

If you thought Nick Fury couldn't look more unimpressed, you're wrong.

A small voice spoke up.

'May I?' Bruce asked tentatively, pointing to the tablet in the scientists hands.

Fury simply nodded, and Bruce took it, and looked at the information.

'It cannot be the Tesseract. The Tesseract is under control and protected on Asgard.' Thor said.

'Uh, how long has this been going on for?' Bruce asked.

'About a month. At first it seemed negligible but now it's getting serious.' Fury replied.

'So what you're asking us to do is take down whatever this threat is, when we know nothing about it?' Natasha said.

Fury was about to inform them that the mission was simply an initial assessment to determine further action, but the tablet beeping furiously in Banner's hands interrupted him.

'That doesn't sound good.' Tony muttered.

Bruce looked very worried. And he was the expert on radiation and energy; he was one of the worlds top scientists on that field. If he was worried, it was serious.

'It just peaked at dangerous levels. This...this is crazy. If we don't control it now...there's gonna be a bigger mess to clean up that just a city.' He said.

Alright. Turns out this was going to be more than an initial assessment. After the last incident with Loki, SHIELD couldn't take any chances. They needed to shut this thing down _now._ Fury was pissed. '_Typical motherfucking Monday.' _He thought.

'But...Wait a sec, that's energy. _Pure _energy. How are we supposed to control that?' Tony exclaimed, looking over Bruce's shoulder at the wildly fluctuating charts and figures. 'And what the hell could produce something like that other than the glowing party cube?'

'Guess we'd better go find out.' Steve said.

'This cannot be possible. The only thing that can produce pure energy is the Tesseract.' Thor said.

'But if you say that it's on Asgard and secure, then something else must be causing this. Something powerful.' Natasha offered.

'There's an aircraft waiting for you on the helipad. The flight plan is programmed in and any equipment you might need is stocked up. There are other special force teams on call should you need assisstance. Good luck.' Agent Hill said.

And with that, the Avengers made their way to the large helipad on the roof of the building, Tony opting to suit up and fly solo alongside, and they headed out to what awaited them.

The destination was far away from any civilisation. Way out in the desert, with mountains rising up from the barren landscape. There were no lone roads winding their way through the dust, no outback shacks or derelict farms. There was nothing here.

Apart from a mysterious projectile, heading straight for a mountain at a blindingly fast speed. It crashed into the rock with a deafening explosion, and the dust slowly settled around the small crater in the side of the mountain, rubble and debris scattering to a halt some distance away.

'What the hell was that?!' Tony yelled. It had to be some sort of weapon; a missile maybe. It had seemingly come out of nowhere and had passed far too quickly for him to lock onto it or for JARVIS to get any sort of reading.

'You're the tech expert, Stark. Maybe it was a weapon of some sort. I mean, out here would be a perfect place to test anything, right? Maybe the energy reading was from a new weapon or something, and someone is doing trial runs in the desert before they decide to do some real damage with it.' Clint thought out loud.

'I couldn't get a reading on it. JARVIS has no idea what it is either.' Tony replied, landing not far from the mountain. Natasha and Clint landed the aircraft and everybody got out.

'Should we go and check it out?' Steve said meekly, not sure it was the best idea. Even Tony thought twice, when he would usually go and investigate fearlessly.

Before anyone could reply, the ground started shaking, as if an earthquake was starting. This was definitely not an earthquake though. This was worse.

Far worse.


	2. Introductions

**XYZ: Thank you very much for your review. I'm glad you liked it! I agree-there is a serious lack of Avengers/DBZ fics. Luckily, I am determined to put that right. In answer to your question: it was not a Saiyan Pod, it was the mysterious OC, getting her ass kicked. You'll find out more about that. I imagine that kind of hurt, being kicked into a mountain. Might bruise the next morning. Enjoy the next chapter, I hope you will like it.**

**Guest: Here you go! Enjoy!**

**I'm thinking of doing a DBZ/Star Trek fic. What do you think? Any suggestions or ideas? Let me know. **

**I have two exams coming next week, so this story will be on a short hiatus until they are done, and then it will be back to kind-of-regular updates! Remember: reviews are great encouragement! They're also a good way to provide opinions and feedback, and I'd love to know what you think, so review away!**

**-Shadow**

* * *

The ground shook more violently and the team started to seriously worry.

They had every reason to.

The mountain exploded, sending rock and debris in all direction, and a bright yellow light blinded them. It shot up into the sky and hovered, dimming to what appeared to be a flame. It was still. It was waiting for something.

'Well that doesn't look like any weapon I've ever seen.' Tony said.

'It appears to be a female humanoid life form, Sir. My readings indicate that the creature is the source of the unusual energy radiation. I strongly suggest defensive action.' JARVIS informed them. So that yellow light was some sort of energy aura then? Interesting.

'Right. So how do we take this thing down?' Clint said, loading a sedation arrow.

'I don't think we have many options.' Natasha said flatly.

'Another energy source at 2 o'clock, Sir.' JARVIS said.

Sure enough, there was another...thing. Some sort of creature headed towards the flame. Before anyone could do anything, both parties fired beams of energy, colliding halfway with a crash of electricity and thunder.

'Looks like we don't have _any_ options; if we get hit by one of those blasts, we'd be fried. They're both emitting crazy levels of energy.' Tony told the team.

'The second life form appears to be a reptilian alien.' JARVIS said.

'Two of them. Great.' Clint muttered

The sky grew darker and the ground shook and cracked. The point where the beams met were moving; the reptile was losing. All of a sudden, the beams cut off and the two fighters collided into vicious hand to hand combat, attacking each other with incredible speed-so fast that their movements were just a blur. Then they vanished. Only to collide in the air again. And again. Over and over, all that could be seen were sonic booms as they collided rapidly, moving erratically in the air. Lightning struck the barren landscape around them; thunder roaring. Suddenly, one of them crashed down to the ground, making a small crater.

It wasn't getting up.

The female appeared over the hideous lizard, roughly grabbing its neck, slowly rising upwards and coming to a halt several meters in the air. She was choking it. It thrashed frantically, limbs flailing wildly. She didn't flinch when it's long, razor tipped tail slashed her. Small bolts of lightning sparked around her. She threw the reptile back into the crater, raised her hand, aimed at it, and fired. The bright ball of energy hit and exploded, the crater doubling in size. No remains were left. No body, no ashes. Nothing but a charred crater in the middle of a desert. The Avengers were stunned. They'd seen some things and dealt with weird stuff but this was a whole new level of "Oh, _shit._"

The woman descended to the edge of the crater. Then turned around.

Tony was the first to react.

He blasted at her, but before the shot got there, she was standing _right in front of him._ He was too slow. She kneed him in the stomach, denting the suit, then jumped up to spin and kick him in the face, sending him flying and skidding to a halt, knocked out cold. So much for defensive action. This time, Thor was the one causing the lighting and thunder. She didn't notice the giant green monster until he tackled her and started punching her. She blasted at his face, which stunned him, giving her a chance to get away. Natasha fired her guns but all the bullets were avoided. Magazines spent, and guns essentially useless, she ran up to the woman but was swiftly assaulted and knocked out. Clint was hit by a couple of energy blasts, knocking him off his feet and leaving burns.

The mighty Avengers were falling, one by one, but this alien wasn't taking the damage too well either. Stumbling, she faced the Hulk. It was bad enough on any given day, but now he was _pissed._ He roared and charged at the woman, but she vanished again, leaving him frantically searching. Then things took a turn for the worse. Hit in the face by Mjolnir, she was down, but not quite out. The Hulk was, however. When he had turned around and finally spotted her, he was in the way of the thunder god's hammer, which hit him in the stomach with incredible force. He was left on the floor, paralyzed in pain. Thor, with Mjolnir back in his grasp, was now aiming it at her, furious that she dared to attack the planet under his protection. With an almighty roar, he launched it, only for it to be caught and thrown back at him, which he wasn't expecting. Caught off guard, it knocked him to the ground, where she viciously attacked him. He barely defended himself from her rapid punches, but kneed the woman in the gut with godly strength and threw her hard to the ground. Blood loss, pain and disorientation were now slowing her down. The tables turned as a very awake and pissed off Tony grabbed the fighter from behind, struggling to hold her. It didn't last long. Natasha carefully got up, walked over and kicked her abruptly in the face. Then Clint shot the arrow, hitting the fighter in the stomach. She ripped it out with a curse, eyes narrowed on him. Tony let go and kicked her in the back. She hit the ground hard. Vision going blurry, the last thing the alien warrior saw was something big and green, immense pain, then she passed out.

"I'm getting real tired of aliens now. I think I'm gonna retire soon, so I don't have to deal with all this bullshit." Tony said, panting. No one else replied, but there was an unspoken agreement that the heroes needed a vacation. Too bad that wasn't going to happen any time soon. Bruce changed back, collapsing in exhaustion. Thor was pissed off about the whole Mjolnir incident. Natasha, Clint and Tony were barely standing, the inflicted injuries taking their toll. They restrained the unconscious woman, returning to the aircraft and heading back to SHIELD HQ. Director Fury was not going to like this. There was no doubt that millions would be made with a swear jar when they got back with their report.

It had been nearly a week since the desert battle, and security was on high alert. The Avengers were still recovering from the injuries, but the worst was healed. They were now gathered underground, in one of the more well equipped science bases. SHIELD's best scientists had been working constantly to solve the puzzle of the alien fighter, who was currently under an induced coma and heavily restrained. The events that had occurred on the desert mission were explained to Fury, and the other directors on the board were informed.

Today was the big day. Time to poke the vicious monster with a stick.

The team filed into the laboratory, forming a semi circle around the table, to which she was tied. The table was tilted forward, so she was almost standing. On Fury's order, one of the scientists injected something and they waited. It didn't take long. A few tense minutes later, she opened her eyes and everyone held their breath, sedative and guards on standby. She blinked a few times, looking at her surroundings and at each face, showing no emotion. Fury stepped forward and she locked her gaze with him.

"Why are you on this planet?" He asked sternly. She didn't reply. He tried again.

"What is your intention here?" Still nothing.

"You came here, picked a fight with another alien, remodeled the landscape and nearly killed my team. You are a deadly threat, and you'd better start talking because I think you owe me an explanation." He growled with narrowed eyes. After nearly a minute of the staring contest, he gave up with an irritated sigh.

"Or what?" She growled. Everyone froze. "Your team no doubt reported my actions. They know exactly what happened. Do you honestly believe this will make a difference?" She asked, looking at the metal bars holding her down. Fury frowned.

"I don't care. What I want to know is what you're doing on this planet and until you tell me, you're going to be spending a lot more time like that." He replied, gesturing to the restraints. She chuckled.

"Humans. So fragile. So narrow minded." Electricity sparked around her. The guards moved in but Fury held up a hand. "For all your technology, you had no idea." She said with a smirk.

"About what, exactly?" Fury countered. She chuckled again.

"About the fact that I have been residing on your planet _long_ before you detected me. I'd say roughly two months. If I hadn't been forced to retaliate to that idiot hunting me down then I have no doubt you would never have found me. Now I come to the conclusion that it was either due to your inferior technology, or I'm _just too good._ I think it may have a lot to do with the latter, but that's possibly a little biased. Unfortunately, I can't stay and chat." She said, breaking free of the table with ease and carefully removing the wires. She blasted at the guards and the scientist with the sedative, knocking them out.

"I must say, I appreciate the care." She said, gesturing to the medical equipment. "Good luck with your research. It won't matter anyway." With that, she smiled, bowing and vanishing. Fury cursed in frustration. There was some good news though, and he was counting on it, because it may just give them vital clues and information.

However, another investigation was being carried out.

On Asgard.


End file.
